Another LC/TZ Hybrid

85RZwade · January 12, 2020, 02:45:04 PM

I started this morning by harvesting some parts from one of the donors, including the front brake caliper I intend to use. Before I crack this thing apart, I'd like to know that I can source replacement parts...

Does anyone recognize this Brembo? I can tell you it was non-standard fitment on an '83 TZ250K.

Any recommendations for a replacement parts source?
Thanks, Wade

teazer · January 12, 2020, 06:23:36 PM

Looks like a P108 fitted to some Paso's.

38mm pistons are probably the same as an F08 which were really common.

85RZwade · January 12, 2020, 07:50:50 PM

Excellent, thank you
Wade

85RZwade · January 13, 2020, 08:51:53 PM

It came apart nicely and looks a little better after a trip through the parts washer.

The bores look nice below the piston seal, but there's a little corrosion above the seal (nearer the pad).

I found pistons and seal kits nicely priced at oppracing. In the meantime, more cleaning and I may pop the other caliper apart to see how it's condition compares.
Wade

85RZwade · January 16, 2020, 01:17:36 AM

These are 38mm pistons (two per caliper) and I'm leaning towards taking the advice to use one caliper. So, referring to the chart Mr. Quenzler provided in Daytona Z's thread "Daytona Special dual disk..." and using his preferred ratio, I'm looking for a master cylinder of 11mm bore diameter. There are a bunch out there, thankfully, and not terribly expensive...but you know how you like what you like? I like remote reservoirs. It's probably related to my age

This is the part where someone replies: "I'll sell you an identifiable name-brand 11mm remote reservoir front master cylinder for peanuts." In the meantime, I'll be searching.
Wade

85RZwade · January 31, 2020, 01:20:29 AM

Well, my research led me to an Aprilia RS125 front master cylinder made by Grimeca. Tough to find, except for a German seller on eBay with a dozen or so. Made an offer, they accepted, I second-guessed my decision...oh well. Levers are available ($$$), rebuild kits not. Found a reference somewhere to Grimeca closing its doors, which would explain the latter

Found a new lever tonight on eBay from a UK seller and pulled the trigger; half the going price including shipping! Must be too good to be true.

received rebuild kit and pistons for the Brembo caliper from OPP, so WHEN the master cylinder parts arrive from afar and IF the cylinder makes pressure, I should have a nice front brake system. Note to self: no eBay after 9:00 p.m.
Wade

85RZwade · February 05, 2020, 06:08:56 PM

Front master cylinder arrived today, and although it doesn't say much for my research skills, I am happy to see it is a Brembo rather than a Grimeca. Finding a kit just got easier.
Wade

85RZwade · February 11, 2020, 01:15:06 AM

Lever landed on my bench today, and it's a peach. Fits the master cylinder, and I'm working on a pivot bolt.

Jspooner · February 11, 2020, 06:15:02 AM

Quote from: 85RZwade on February 11, 2020, 01:15:06 AM
Lever landed on my bench today, and it's a peach. Fits the master cylinder, and I'm working on a pivot bolt.

How about the rest of the bike............got any pics?

85RZwade · February 11, 2020, 09:01:43 PM

Point taken! Not much is assembled yet, but here's the plan: start with this '75 RD350

and update it...at least a decade or so, with a water-cooled '82 RD350LC engine

and suspension and brakes from an '83 TZ250K

85RZwade · February 11, 2020, 09:13:21 PM

I'm using a single disc up front, so I removed one from the wheel

I was surprised how heavy the discs were: 5.23 lbs solid, 4.73 lbs drilled. Drilled disc it is, then! This bike came to me with the Brembo 2-piston calipers above, so I'll make one out of the best parts and the new pistons and seal kit. Here's the Brembo master cylinder and lever

Hopefully the braided brake line can be reused, but we'll see if everything lines up correctly.

Jspooner · February 11, 2020, 09:43:34 PM

Looks like you have a good start. I'll give you a pointer on using that LC engine in the RD frame. Im assuming you will be rebuilding the bottom end so it will be split and it needs to be to do this anyway. You can take an AC bottom case half and an LC top case half and bolt them together. You can then put that in the AC frame and the bottom front and bottom rear mounts will properly align the engine while you fab mounts for the LC engine since they are mounted by the top case half only. Once you have those mounts fabbed you can put the assembled LC cases in the frame and cut away the unneeded mounts from the AC engine and also fab mounts for the tie bars if you plan on using them. This is how I did mine since I am using an LC bottom end in a TR3 frame (same mounts as an RD).

85RZwade · February 11, 2020, 10:12:36 PM

Awesome, thanks for the tip. I haven't looked closely enough yet to know if I'll be able to mimic the TZ rear engine mount:

It might be hard to see in this crappy picture, but the rear engine mount is concentric with the swingarm pivot. If it doesn't conflict with the AC frame, I'll fab one suitable for the LC cases. I think.

Jspooner · February 11, 2020, 10:25:49 PM

Next time I'm out in the shop I'll take some pics of my mounts and post them.

85RZwade · February 11, 2020, 10:36:55 PM

I have a "new" set of DG expansion chambers...they were inexpensive once upon a time, on close out when I worked at a Yamaha dealer. I don't love them, but I own them, so they might go on, but before possibly modifying them to fit (that's a lot of commas), are pipes designed for an air-cooled 350 suitable for the liquid-cooled 350? Kinda leaning towards selling the DGs off to help finance something sexier.

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Another LC/TZ Hybrid